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The power steering fluid may also be red. The power steering reservoir is located at the front, too.

The 08 ps fluid is chf11s which is more greenishish in color if my memory is right. If original fill probably dark brown or black now.

I would look at the trans cooler lines towards the bottom of the radiator towards expansion tank.

Also how thick is the fluid and what does it smell like? Is it more watery? If someone replaced the blue antifreeze with dex cool or g85 coolant it could be the expansion tank.

The first two things that I would do is 1) remove the top engine cover (4 torx screws and intake snorkel to look around top of engine
2) get the car up on jack stands and remove bottom engine cover 4 17mm bolts by tranny and about 12 8 or 9mm bolts around the perimeter.